In an audio device, a white connector and a red connector are often used to distinguish a left audio channel and a right audio channel. In general, the white connector connects the left audio channel to a speaker of the left audio channel, the red connector connects the right audio channel to a speaker of the right audio channel, so that sounds from the left audio channel are playing in the speaker of the left audio channel, sounds from the right audio channel are playing in the speaker of the right audio channel.